The invention relates to a radial seal and more particularly to a radial combustion air seal for a rotary combustor in a municipal solid waste incinerator.
The rotary combustor of a municipal solid waste incinerator is made of a circular array of cooling pipes spaced apart by a perforated web. The combustor is inclined so the municipal solid waste which enters the upper end of the rotary combustor tumbles down during combustion and exits the lower end as the combustor rotates. Combustion air is supplied to the ignited waste through the perforated web in varying amounts from a divided windbox as the burning waste tumbles to the lower end of the combustor. Since the amount of combustion air supplied from each portion of the wind box varies depending on the waste being burned, accurate control of the combustion air in each portion of the windbox requires reliable radial seals between the various portions of the windbox.